Grade 3 - Shape and Space
Standard 3.SS.3 - Practice finding the appropriate length of various objects. Understand the approximate scale of different metric units.
Included Skills: Measurement
Demonstrate understanding of linear measurement (cm and m) including: • selecting and justifying referents • generalizing the relationship between cm and m • estimating length and perimeter using referents • measuring and recording length, width, height, and perimeter. • Observe and describe situations relevant to self, family, and community that involve measuring lengths, including perimeter, in cm or m. • Measure and compare different lengths on 3-D objects to select personally relevant referents for 1 cm, 10 cm, and 1 m. • Create models to generalize a numerical relationship between cm and m (i.e., 100 cm is equivalent to 1 metre). • Pose and solve situational questions that involve the estimating or measuring of length (including perimeter) using cm or m. • Identify and determine the length of the dimensions of a personally relevant 2-D shape or 3-D object. • Explain why sometimes different names are used for different length measurements (e.g., height, width, or depth). • Sketch a line segment of an estimated length and describe the strategy used. • Draw a line segment of a given length and explain the process used. • Relate measuring using a referent for 10 cm to skip counting quantities by 10s. • Create a picture of a 2-D shape with specified length and width (or length and height) and explain whether the 2-D shape was constructed using estimates or actual lengths. • Measure and record the perimeter of regular 2-D polygons and circles located on 3-D objects, and explain the strategy used. • Measure and record the perimeter of a given irregular 2-D shape, and explain the strategy used. • Construct or draw more than one 2-D shape for the same given perimeter (cm, m). • Estimate the perimeter of a given 2-D shape (cm, m) using personal referents and explain the strategies used. • Critique the statement "perimeter is a linear measurement". • Sort a set of 2-D shapes into groups with equal perimeters.